UnanchoredRegex

scala.util.matching.UnanchoredRegex
trait UnanchoredRegex extends Regex

A Regex that finds the first match when used in a pattern match.

Attributes

See also:
Source:
Regex.scala
Graph
Supertypes
class Regex
class Object
trait Matchable
class Any

Members list

Concise view

Value members

Concrete methods

override protected def runMatcher(m: Matcher): Boolean

Attributes

Definition Classes
Source:
Regex.scala

Create a new Regex with the same pattern, but no requirement that the entire String matches in extractor patterns and Regex#matches.

Create a new Regex with the same pattern, but no requirement that the entire String matches in extractor patterns and Regex#matches.

Normally, matching on date behaves as though the pattern were enclosed in anchors, "^pattern$".

The unanchored Regex behaves as though those anchors were removed.

Note that this method does not actually strip any matchers from the pattern.

Calling anchored returns the original Regex.

val date = """(\d\d\d\d)-(\d\d)-(\d\d)""".r.unanchored

val date(year, month, day) = "Date 2011-07-15"                       // OK

val copyright: String = "Date of this document: 2011-07-15" match {
  case date(year, month, day) => s"Copyright $year"                  // OK
  case _                      => "No copyright"
}

Attributes

Returns:

The new unanchored regex

Definition Classes
Source:
Regex.scala

Inherited methods

Attributes

Inherited from:
Regex
Source:
Regex.scala

Return all non-overlapping matches of this Regex in the given character sequence as a scala.util.matching.Regex.MatchIterator, which is a special scala.collection.Iterator that returns the matched strings but can also be queried for more data about the last match, such as capturing groups and start position.

Return all non-overlapping matches of this Regex in the given character sequence as a scala.util.matching.Regex.MatchIterator, which is a special scala.collection.Iterator that returns the matched strings but can also be queried for more data about the last match, such as capturing groups and start position.

A MatchIterator can also be converted into an iterator that returns objects of type scala.util.matching.Regex.Match, such as is normally returned by findAllMatchIn.

Where potential matches overlap, the first possible match is returned, followed by the next match that follows the input consumed by the first match:

val hat  = "hat[^a]+".r
val hathaway = "hathatthattthatttt"
val hats = hat.findAllIn(hathaway).toList                     // List(hath, hattth)
val pos  = hat.findAllMatchIn(hathaway).map(_.start).toList   // List(0, 7)

To return overlapping matches, it is possible to formulate a regular expression with lookahead (?=) that does not consume the overlapping region.

val madhatter = "(h)(?=(at[^a]+))".r
val madhats   = madhatter.findAllMatchIn(hathaway).map {
  case madhatter(x,y) => s"$x$y"
}.toList                                       // List(hath, hatth, hattth, hatttt)

Attempting to retrieve match information after exhausting the iterator results in java.lang.IllegalStateException. See scala.util.matching.Regex.MatchIterator for details.

Attributes

source

The text to match against.

Returns:

A scala.util.matching.Regex.MatchIterator of matched substrings.

Example:

for (words <- """\w+""".r findAllIn "A simple example.") yield words
Inherited from:
Regex
Source:
Regex.scala

Return all non-overlapping matches of this regexp in given character sequence as a scala.collection.Iterator of scala.util.matching.Regex.Match.

Return all non-overlapping matches of this regexp in given character sequence as a scala.collection.Iterator of scala.util.matching.Regex.Match.

Attributes

source

The text to match against.

Returns:

A scala.collection.Iterator of scala.util.matching.Regex.Match for all matches.

Example:

for (words <- """\w+""".r findAllMatchIn "A simple example.") yield words.start
Inherited from:
Regex
Source:
Regex.scala

Return an optional first matching string of this Regex in the given character sequence, or None if there is no match.

Return an optional first matching string of this Regex in the given character sequence, or None if there is no match.

Attributes

source

The text to match against.

Returns:

An scala.Option of the first matching string in the text.

Example:

"""\w+""".r findFirstIn "A simple example." foreach println // prints "A"
Inherited from:
Regex
Source:
Regex.scala

Return an optional first match of this Regex in the given character sequence, or None if it does not exist.

Return an optional first match of this Regex in the given character sequence, or None if it does not exist.

If the match is successful, the scala.util.matching.Regex.Match can be queried for more data.

Attributes

source

The text to match against.

Returns:

A scala.Option of scala.util.matching.Regex.Match of the first matching string in the text.

Example:

("""[a-z]""".r findFirstMatchIn "A simple example.") map (_.start) // returns Some(2), the index of the first match in the text
Inherited from:
Regex
Source:
Regex.scala

Return an optional match of this Regex at the beginning of the given character sequence, or None if it matches no prefix of the character sequence.

Return an optional match of this Regex at the beginning of the given character sequence, or None if it matches no prefix of the character sequence.

Unlike findFirstMatchIn, this method will only return a match at the beginning of the input.

Attributes

source

The text to match against.

Returns:

A scala.Option of the scala.util.matching.Regex.Match of the matched string.

Example:

"""\w+""".r findPrefixMatchOf "A simple example." map (_.after) // returns Some(" simple example.")
Inherited from:
Regex
Source:
Regex.scala

Return an optional match of this Regex at the beginning of the given character sequence, or None if it matches no prefix of the character sequence.

Return an optional match of this Regex at the beginning of the given character sequence, or None if it matches no prefix of the character sequence.

Unlike findFirstIn, this method will only return a match at the beginning of the input.

Attributes

source

The text to match against.

Returns:

A scala.Option of the matched prefix.

Example:

"""\p{Lower}""".r findPrefixOf "A simple example." // returns None, since the text does not begin with a lowercase letter
Inherited from:
Regex
Source:
Regex.scala

Returns whether this Regex matches the given character sequence.

Returns whether this Regex matches the given character sequence.

Like the extractor, this method takes anchoring into account.

Attributes

source

The text to match against

Returns:

true if and only if source matches this Regex.

See also:
Example:

"""\d+""".r matches "123" // returns true
Inherited from:
Regex
Source:
Regex.scala

Attributes

Inherited from:
Regex
Source:
Regex.scala
def replaceAllIn(target: CharSequence, replacer: Match => String): String

Replaces all matches using a replacer function.

Replaces all matches using a replacer function. The replacer function takes a scala.util.matching.Regex.Match so that extra information can be obtained from the match. For example:

import scala.util.matching.Regex
val datePattern = new Regex("""(\d\d\d\d)-(\d\d)-(\d\d)""", "year", "month", "day")
val text = "From 2011-07-15 to 2011-07-17"
val repl = datePattern replaceAllIn (text, m => s"${m group "month"}/${m group "day"}")

In the replacement String, a dollar sign ($) followed by a number will be interpreted as a reference to a group in the matched pattern, with numbers 1 through 9 corresponding to the first nine groups, and 0 standing for the whole match. Any other character is an error. The backslash (\) character will be interpreted as an escape character and can be used to escape the dollar sign. Use Regex.quoteReplacement to escape these characters.

Attributes

replacer

The function which maps a match to another string.

target

The string to match.

Returns:

The target string after replacements.

Inherited from:
Regex
Source:
Regex.scala
def replaceAllIn(target: CharSequence, replacement: String): String

Replaces all matches by a string.

Replaces all matches by a string.

In the replacement String, a dollar sign ($) followed by a number will be interpreted as a reference to a group in the matched pattern, with numbers 1 through 9 corresponding to the first nine groups, and 0 standing for the whole match. Any other character is an error. The backslash (\) character will be interpreted as an escape character and can be used to escape the dollar sign. Use Regex.quoteReplacement to escape these characters.

Attributes

replacement

The string that will replace each match

target

The string to match

Returns:

The resulting string

Example:

"""\d+""".r replaceAllIn ("July 15", "<NUMBER>") // returns "July <NUMBER>"
Inherited from:
Regex
Source:
Regex.scala
def replaceFirstIn(target: CharSequence, replacement: String): String

Replaces the first match by a string.

Replaces the first match by a string.

In the replacement String, a dollar sign ($) followed by a number will be interpreted as a reference to a group in the matched pattern, with numbers 1 through 9 corresponding to the first nine groups, and 0 standing for the whole match. Any other character is an error. The backslash (\) character will be interpreted as an escape character and can be used to escape the dollar sign. Use Regex.quoteReplacement to escape these characters.

Attributes

replacement

The string that will replace the match

target

The string to match

Returns:

The resulting string

Inherited from:
Regex
Source:
Regex.scala
def replaceSomeIn(target: CharSequence, replacer: Match => Option[String]): String

Replaces some of the matches using a replacer function that returns an scala.Option.

Replaces some of the matches using a replacer function that returns an scala.Option. The replacer function takes a scala.util.matching.Regex.Match so that extra information can be obtained from the match. For example:

import scala.util.matching.Regex._

val vars = Map("x" -> "a var", "y" -> """some $ and \ signs""")
val text = "A text with variables %x, %y and %z."
val varPattern = """%(\w+)""".r
val mapper = (m: Match) => vars get (m group 1) map (quoteReplacement(_))
val repl = varPattern replaceSomeIn (text, mapper)

In the replacement String, a dollar sign ($) followed by a number will be interpreted as a reference to a group in the matched pattern, with numbers 1 through 9 corresponding to the first nine groups, and 0 standing for the whole match. Any other character is an error. The backslash (\) character will be interpreted as an escape character and can be used to escape the dollar sign. Use Regex.quoteReplacement to escape these characters.

Attributes

replacer

The function which optionally maps a match to another string.

target

The string to match.

Returns:

The target string after replacements.

Inherited from:
Regex
Source:
Regex.scala
def split(toSplit: CharSequence): Array[String]

Splits the provided character sequence around matches of this regexp.

Splits the provided character sequence around matches of this regexp.

Attributes

toSplit

The character sequence to split

Returns:

The array of strings computed by splitting the input around matches of this regexp

Inherited from:
Regex
Source:
Regex.scala
override def toString: String

The string defining the regular expression

The string defining the regular expression

Attributes

Definition Classes
Inherited from:
Regex
Source:
Regex.scala

Tries to match on a scala.util.matching.Regex.Match.

Tries to match on a scala.util.matching.Regex.Match.

A previously failed match results in None.

If a successful match was made against the current pattern, then that result is used.

Otherwise, this Regex is applied to the previously matched input, and the result of that match is used.

Attributes

Inherited from:
Regex
Source:
Regex.scala

Tries to match the String representation of a scala.Char.

Tries to match the String representation of a scala.Char.

If the match succeeds, the result is the first matching group if any groups are defined, or an empty Sequence otherwise.

For example:

val cat = "cat"
// the case must consume the group to match
val r = """(\p{Lower})""".r
cat(0) match { case r(x) => true }
cat(0) match { case r(_) => true }
cat(0) match { case r(_*) => true }
cat(0) match { case r() => true }     // no match

// there is no group to extract
val r = """\p{Lower}""".r
cat(0) match { case r(x) => true }    // no match
cat(0) match { case r(_) => true }    // no match
cat(0) match { case r(_*) => true }   // matches
cat(0) match { case r() => true }     // matches

// even if there are multiple groups, only one is returned
val r = """((.))""".r
cat(0) match { case r(_) => true }    // matches
cat(0) match { case r(_,_) => true }  // no match

Attributes

c

The Char to match

Returns:

The match

Inherited from:
Regex
Source:
Regex.scala

Tries to match a java.lang.CharSequence.

Tries to match a java.lang.CharSequence.

If the match succeeds, the result is a list of the matching groups (or a null element if a group did not match any input). If the pattern specifies no groups, then the result will be an empty list on a successful match.

This method attempts to match the entire input by default; to find the next matching subsequence, use an unanchored Regex.

For example:

val p1 = "ab*c".r
val p1Matches = "abbbc" match {
  case p1() => true               // no groups
  case _    => false
}
val p2 = "a(b*)c".r
val p2Matches = "abbbc" match {
  case p2(_*) => true             // any groups
  case _      => false
}
val numberOfB = "abbbc" match {
  case p2(b) => Some(b.length)    // one group
  case _     => None
}
val p3 = "b*".r.unanchored
val p3Matches = "abbbc" match {
  case p3() => true               // find the b's
  case _    => false
}
val p4 = "a(b*)(c+)".r
val p4Matches = "abbbcc" match {
  case p4(_*) => true             // multiple groups
  case _      => false
}
val allGroups = "abbbcc" match {
  case p4(all @ _*) => all mkString "/" // "bbb/cc"
  case _            => ""
}
val cGroup = "abbbcc" match {
  case p4(_, c) => c
  case _        => ""
}

Attributes

s

The string to match

Returns:

The matches

Inherited from:
Regex
Source:
Regex.scala

Inherited fields

Attributes

Inherited from:
Regex
Source:
Regex.scala